I'm a little slow on this one. Riya has shifted strategy. They are now indexing the web to create a visual search engine. Munjal Shah, the founder of Riya, has more on his blog:

Where are we going? Riya 2.0 will be a web-wide (public) visual search engine that uses face and image similarity to search the web. We are calling this new kind of public web search: Visual Search. Why? Because you will be able to search by clicking on / submitting a photo instead of having to type in text.

We are 100% focused on building the core technology right now and starting to crawl the web. When will it be available? Not for a while. Probably three or more months. Why are we talking about it now? Our crawlers are going out there and I want webmasters to let them in...;-). What will happen to Riya 1.0 and the personal search based upon face recognition? I will remain something you can do once you register for our search engine and create an account. You will even be able to do face similarity on your own photos without making them public.